Field of the Invention
The present invention relates to a connection structure and a connection method for a terminal fitting.
Description of Related Art
There has been known a connection structure in which connection plates of a plurality of terminal fittings, to which grounding electric wires have been connected, are put on top of one another, a common bolt is inserted into mounting holes provided in the connection plates to thereby bolt and fasten the connection plates to a grounding surface (such as a predetermined place of a vehicle body), so that the grounding electric wires can be conductively connected to the grounding surface in a lump through the terminal fittings put on top of one another (for example, see Patent Literature 1: JP-A-2012-190749).
[Patent Literature 1] JP-A-2012-190749
According to a related art, in a structure in which terminal fittings put on top of one another are fastened by a bolt, the terminal fittings connected to grounding electric wires respectively are put on top of one another and fastened by the bolt. Therefore, the weight increases as the number of grounding electric wires increases. In addition, the thickness of the terminal fittings put on top of one another increases as the number of grounding electric wires increases. Thus, a large space for receiving the terminal fittings has to be secured above the grounding surface. In addition, much working time is required for fastening work while adjusting the nut length or the bolt length in accordance with the terminal fittings to be put on top of one another.
In addition, in order to conductively connect a plurality of grounding electric wires in a lump, it can be also considered to use a joint connector in which connection terminals connected to the grounding electric wires are inserted into a housing accommodating joint terminals to thereby conductively connect the grounding electric wires in a lump through the joint terminals while holding the connection terminals inside the housing. However, in the case of the joint connector, a holding mechanism (such as a lock lance) for holding the connection terminals inside the housing has to be provided. It is therefore difficult to miniaturize the housing. In addition, since the housing provided with the holding mechanism is required, the cost increases inevitably.
In addition, due to fastening by a bolt, reliability in connection may deteriorate after the connection because the bolt is loosened. In this case, when the connection terminals are crimped and fastened to the terminal fittings, a firm connection structure can be obtained. However, when the connection terminals and the terminal fittings are crimped by a crimping machine, there is a fear that their postures cannot be stabilized relatively to each other but a variation may occur in crimping strength.